Injections of various substances into avian eggs have been employed to decrease post-hatch mortality rates, increase the potential growth rates or eventual size of the resulting chicken, and even to influence the gender determination of the embryo. Similarly, injections of antigens into live eggs have been employed to incubate various substances used in vaccines which have human or animal medicinal or diagnostic applications. Examples of substances that have been used for, or proposed for, in ovo injection include vaccines, antibiotics and vitamins. In addition, removal of material from avian eggs has been employed for various purposes, such as testing and vaccine harvesting.
Poultry eggs (hereinafter “eggs”) may be typically inoculated on or about the eighteenth day of incubation using in ovo injection systems. Typically, eggs are held in flats on racks in carts for incubation in relatively large incubators. At a selected time, typically on the eighteenth day of age, a cart of eggs is removed from the incubator for the purposes of inoculation. In some instances, all eggs are inoculated, including non-viable eggs. In other instances, however, separating out non-viable eggs (namely, dead eggs, rotted eggs, empties, and clear eggs) and inoculating only the live eggs may occur at the eighteenth day of incubation.
Conventionally, devices for injecting material into eggs and for removing material from eggs are configured to pierce and enter an egg along a generally vertical direction. Eggs are generally positioned in an upright, vertical orientation with the longitudinal axis of the egg substantially aligned with vertical. Egg injection techniques incorporate aseptic (sterile) introduction of a needle and/or punch through the shell of an egg and subsequently through the membrane below the blunt end of an egg. The sterility of the injection solution (diluent or media) should be maintained. The introduction of bacteria, microbes, viruses and other pathogens into a developing embryo may be lethal as well as cause depressed growth and development if the embryo survives.
Typically, in ovo injection systems address the issue of pathogen invasion through the use of sanitizing fluid (e.g., a buffered chlorine solution) that bathes various components of the injection device (e.g., the needle and/or punch) between egg injections. In this regard, the exterior and interior (lumen) of punch/needle injection devices may be flushed with sanitizing fluid between injections.
FIG. 1 illustrates a conventional manifold assembly 1 implemented in a sanitization system for an in ovo injection system. The manifold assembly 1 includes a plurality of fluid check valves 5 coupled to an upper manifold 2. Sanitizing fluid is supplied to each fluid check valve 5. The sanitizing fluid opens the fluid check valves 5 and fills adjacent wells defined within the upper manifold 2. Air is supplied to the upper manifold 2 from both ends via elbow connectors 7 and air check valves 8. Air pressure pushes the sanitizing fluid down into a plurality of fluid paths at the bottom of each well and extending into a lower manifold 3 coupled to the upper manifold 2, such that sanitizing fluid is delivered to individual egg injection devices via appropriate tubing. The fluid check valves 5 prevent fluid from backing up to a splitter manifold that supplies fluid to each fluid check valve 5 via a pump assembly.
Such conventional systems, however, implement complex sanitization systems having valves and other components that require significant servicing and maintenance efforts. In addition, such systems may provide variability in the volume of sanitizing fluid provided to each injection device.
Accordingly, it would be desirable to provide an egg processing system capable of minimizing the variation in dispense volume of sanitizing fluid among a plurality of individual egg injection devices, while also decreasing the servicing efforts to maintain a sanitization system of the egg processing system in a functioning manner. Furthermore, it would be desirable to provide an associated method that would facilitate improved performance with respect to delivering consistent amounts of sanitizing fluid among a plurality of individual egg injection devices, as well as improving dispense accuracy.